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Chemical Oceanography, 4th Edition
rapidly removed; the refractory DOC is slowly lost with time. The values decrease from 40 to
36 M in the deep waters as the waters move from the North Atlantic to the North Pacific
over a period of about 500 yr. A section of the DOC in the surface waters of the Atlantic
Ocean from the surface to 500 m is shown in Figure 9.38. The highest values are in the
surface waters. The upwelling off the coast of Africa brings up lower waters of DOC from
the deep. The global distribution of DOC in the world oceans is shown in Figure 9.39. The
deep values of DOC follow the circulation of the deep waters. The deep Pacific waters have
EQ
40
50
60
70
80
10°N
20°N
30°N
40°N
50°N
60°N
60°N
40°N
20°N
40°W 20°W
Ocean Data View
Ocean Data View
EQ
500
Depth (m)
Doc (UMOL/Kg)
400
300
200
100
Figure 9.38
Section of dissolved organic carbon in the North Atlantic (A16). (From Hansell, D.A., personal communication.)
1000
400
200
0
80
70
60
50
Doc (µmol kg –1 )
40
2000
3000
Depth (m)
4000
5000
6000
60°N
40°
20°
0°
20°
40°
60°S
6 0 ° S
4 0 °
2 0 °
2 0 °
4 0 °
6 0 ° N
6 0 0 0
5 0 0 0
4 0 0 0
Depth
(m)
Depth
(m)
3 0 0 0
2 0 0 0
1 0 0 0
4 0 0
2 0 0
0
0 °
6000
2 0 ° N
5000
4000
3000
2000
1000
400
200
0
Figure 9.39
The global distribution of DOC in the world oceans. (From Hansell, D.A., et al., Oceanography, 12, 203–211, 2009.
With permission.)